Mary Jane Sterling - Algebra I for Dummies

Algebra I For Dummies, 2nd Edition

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Library of Congress Control Number: 2010920659

ISBN 978-1-119-29357-6 (pbk); ISBN 978-1-119-29759-8 (ebk); ISBN 978-1-119-29756-7 (ebk)

Algebra I For Dummies, 2nd Edition (9781119293576) was previously published as Algebra I For Dummies, 2nd Edition (9780470559642). While this version features a new Dummies cover and design, the content is the same as the prior release and should not be considered a new or updated product.

1. Table of Contents

Let me introduce you to algebra. This introduction is somewhat like what would happen if I were to introduce you to my friend Donna. Id say, This is Donna. Let me tell you something about her. After giving a few well-chosen tidbits of information about Donna, Id let you ask more questions or fill in more details. In this book, you find some well-chosen topics and information, and I try to fill in details as I go along.

As you read this introduction, youre probably in one of two situations:

• Youve taken the plunge and bought the book.
• Youre checking things out before committing to the purchase.

In either case, youd probably like to have some good, concrete reasons why you should go to the trouble of reading and finding out about algebra.

One of the most commonly asked questions in a mathematics classroom is, What will I ever use this for? Some teachers can give a good, convincing answer. Others hem and haw and stare at the floor. My favorite answer is, Algebra gives you power. Algebra gives you the power to move on to bigger and better things in mathematics. Algebra gives you the power of knowing that you know something that your neighbor doesnt know. Algebra gives you the power to be able to help someone else with an algebra task or to explain to your child these logical mathematical processes.

Algebra is a system of symbols and rules that is universally understood, no matter what the spoken language. Algebra provides a clear, methodical process that can be followed from beginning to end. Its an organizational tool that is most useful when followed with the appropriate rules. What power! Some people like algebra because it can be a form of puzzle-solving. You solve a puzzle by finding the value of a variable. You may prefer Sudoku or Ken Ken or crosswords, but it wouldnt hurt to give algebra a chance, too.

This book isnt like a mystery novel; you dont have to read it from beginning to end. In fact, you can peek at how it ends and not spoil the rest of the story.

I divide the book into some general topics from the beginning nuts and bolts to the important tool of factoring to equations and applications. So you can dip into the book wherever you want, to find the information you need.

Throughout the book, I use many examples, each a bit different from the others, and each showing a different twist to the topic. The examples have explanations to aid your understanding. (What good is knowing the answer if you dont know how to get the right answer yourself?)

The vocabulary I use is mathematically correct and understandable. So whether youre listening to your teacher or talking to someone else about algebra, youll be speaking the same language.

Along with the how, I show you the why. Sometimes remembering a process is easier if you understand why it works and dont just try to memorize a meaningless list of steps.

I dont use many conventions in this book, but you should be aware of the following:

• When I introduce a new term, I put that term in italics and define it nearby (often in parentheses).